Generally, antennas for transmitting/receiving radio waves can be classified into a road antenna, and a micro strip antenna, etc. Recently, according to the trend of reduction in the thickness and the size of various terminals, space for an antenna to be housed in the terminal is reduced. Therefore, an extendable road antenna has become commercially available, whose length is shortened to be housed and lengthened to be used according to its usable frequency bands as needed.
According to recent rapid increase in the use of terminals provided with a digital multimedia broadcasting (DMB) function, it becomes the trend that many terminals are employing a swivel antenna, which allows use of an extendable road antenna bendable in various angles in order to receive good quality of radio waves.
FIG. 1 illustrates a conventional swivel antenna inserted into a terminal, and FIG. 2 illustrates the swivel antenna in FIG. 1, which has been extended and is swiveling. Further, FIG. 3 illustrates a conventional swivel antenna to be inserted into a terminal.
Referring to FIGS. 1 and 2, a conventional swivel antenna 10 includes a power feeding unit 11 electrically connected to a terminal 20, an antenna unit 12 folded in multiple stages, and a hinge unit 13 provided between the power feeding unit 11 and the antenna unit 12. In normal times, the swivel antenna 10 is folded in multiple stages to be seated in a space 20a provided in the terminal 20. In contrast, while receiving radio waves, the stages of the antenna unit 12 are extended for use of the swivel antenna 10. Here, the antenna unit 12 includes a whip antenna 12a with elasticity, and thus is prevented from damage when the antenna unit 12 is swiveled by the hinge unit 13. This swivel antenna 10 swivels in a predetermined direction R1 around a hinge pin 13a of the hinge unit 13 as an axis.
In the above-mentioned conventional swivel antenna 10, force is applied from the upper portion to the lower portion of the antenna unit 12 in order to insert the antenna unit 12 folded in the multiple stages into the terminal 20. However, as shown in FIG. 2, if a force F1 in an inclined direction is applied to the antenna unit 12, the hinge unit 13 is bent in a direction R2 opposite to a bending direction, resulting in cracks in a recess portion 13b thereof. The above deformation or damage of the hinge unit 13 decreases durability of the swivel antenna 10, and leads to customer dissatisfaction.